Battery electronics for batteries associated with electric or hybrid vehicles present several challenges in managing the connections between batteries, as well as monitoring and managing battery output. Existing IC battery monitor chip architecture includes either a serial or a parallel communication link from the battery monitor chip to a system controller, the system controller coordinating all battery monitor chips in a system and gathering data therefrom while also controlling charge balancing of the individual batteries.
As electric or hybrid vehicles typically include a plurality of batteries, these individual batteries are each managed by an associated battery monitor chip. In order for the plurality of batteries to behave as a single, larger battery, each respective battery monitor chip is in signal communication with the system controller.
Many modern battery monitor IC's support a “serial daisy chain” method of connecting battery monitor chips together, thereby avoiding the associated costs and complexities of serial isolators between the system controller and each battery monitor chip. However, by using the “serial daisy chain,” a circuit in the battery system is created whereby if any of the electrical connections included in the serial link between each respective battery monitor chip of the plurality of battery monitor chips in a “serial daisy chain” form an open-circuit or a short-circuit to an adjacent node, then serial communication fails for each battery monitor chip on the serial chain.
Without a redundant communication link between each battery monitor chip of the plurality of battery monitor chips, a failure in the serial link between each battery monitor chip may result in the shutdown of the entire battery system.
While existing devices serve their intended purposes, what is needed is a low cost and robust solution to the single-point failure modes in the serial daisy chain links provided by the creation of a symmetrical and redundant serial link.